Matrix Addition -- from Wolfram MathWorld
mathworld.wolfram.com › MatrixAdditionDec 17, 2021 · Denote the sum of two matrices A and B (of the same dimensions) by C=A+B. The sum is defined by adding entries with the same indices c_(ij)=a_(ij)+b_(ij) over all i and j. For example, [a_(11) a_(12); a_(21) a_(22)]+[b_(11) b_(12); b_(21) b_(22)]=[a_(11)+b_(11) a_(12)+b_(12); a_(21)+b_(21) a_(22)+b_(22)].
Matrix Operations—Wolfram Language Documentation
reference.wolfram.com › language › guideThe Wolfram Language's matrix operations handle both numeric and symbolic matrices, automatically accessing large numbers of highly efficient algorithms. The Wolfram Language uses state-of-the-art algorithms to work with both dense and sparse matrices, and incorporates a number of powerful original algorithms, especially for high-precision and symbolic matrices.
Using Wolfram Alpha for Matrices
web.math.ucsb.edu › ~kgracekennedy › WolframAlphaWriting Matrices in Mathematica (Wolfram Alpha) First let’s make a matrix like the one on your first worksheet. Matrices are written with braces, {}. Within the braces we list the rows with more braces. So a matrix with four rows is written {{Row1},{Row2},{Row3},{Row4}}. Each row is separated by a comma and each entry is separated by a comma. The matrix in our Worksheet 1 is written